21501553501133 has 2 divisors, whose sum is σ = 21501553501134. Its totient is φ = 21501553501132.

The previous prime is 21501553501081. The next prime is 21501553501171. The reversal of 21501553501133 is 33110535510512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11846352073609 + 9655201427524 = 3441853^2 + 3107282^2 .

It is a cyclic number.

It is not a de Polignac number, because 21501553501133 - 2²⁸ = 21501285065677 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21501553501093 and 21501553501102.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21501553501193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750776750566 + 10750776750567.

It is an arithmetic number, because the mean of its divisors is an integer number (10750776750567).

Almost surely, 2^{21501553501133} is an apocalyptic number.

It is an amenable number.

21501553501133 is a deficient number, since it is larger than the sum of its proper divisors (1).

21501553501133 is an equidigital number, since it uses as much as digits as its factorization.

21501553501133 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 33750, while the sum is 35.

The spelling of 21501553501133 in words is "twenty-one trillion, five hundred one billion, five hundred fifty-three million, five hundred one thousand, one hundred thirty-three".